Moisture-extraction pattern, phasic water use and phasic growth in groundnut (Arachis hypogaea) under varying moisture regime and groundwater-table condition

An experiment conducted during summer 1992 and 1993 with groundnut (Arachis hypogaea L.) on moisture-extraction pattern, phasic water use and growth at Chiplima showed that moisture-extraction increased with lowering of groundwater-table. On an average, crop extracted 18.6 cm water from 60 cm profile under 50 ± 10 cm water-table depth which increased to 25.2 cm and 26.7 cm at 90 ± 10 and 110 ± 10 cm water-table depth respectively. Extraction was the maximum (9.12 cm) at surface layer of 0–15 cm which accounted for 39.9% of the total extraction. It reduced to 7.31 cm (31.6%), 4.53 cm (18.7%) and 2.54 cm (9.8%) with increase in profile depth by 15 cm up to 60 cm profile respectively. Groundnut used the maximum water of 3.11 cm/day, with maximum growth in terms of crop-growth rate (10.18 g/m²/day) and net assimilation rate (3.31 g/m²/d) during 56–90 days of its growth. Water-use showed significant positive correlation with pod yield at lowest water-table depth, ‘r’ value of 0.994** being the maximum.